It is known that if the statistics are sufficient for validation of CLT [1]}, then the experimentally measured results should always be consistent with the true value within 1\(\sigma \) , 2\(\sigma \)  and 3\(\sigma \)  of uncertainties with probability of 68.3\(\%\) , 95.5\(\%\)  and 99.7\(\%\) , respectively. For most of the measurements, such as the mean of the net-proton number, the required statistics for CLT are easily achieved in experiments. In this case, within the uncertainties, the mean of the measured observable needs to be a real value and independent of the statistics. i.e.,
\(\left<X\right>_{n_{1}} = \left<X\right>_{n_{2}} = \left<X\right>_{n_{3}},\) 
